Carbon monoxide can be lethal at concentrations of less
than 0.1%. The kinetics and mechanism of its toxicology have
been described elegantly by Coburn et al. (J. Clin.
Invest. 1965, 44, 1899−1910): CO combines readily with
blood hemoglobin to form carboxyhemoglobin (COHb). When
a subject is exposed to potentially hazardous levels of
CO, however, the achievement of the equilibrium level of
COHb in the bloodstream requires a number of hours. The
Coburn equation is complex, using a number of input
variables. What is desired is a simple equation, requiring
as input only two or three readily available parameters, that
will provide a good estimate of COHb concentration with
time. Previous efforts to develop such an equation are
reviewed. This work provides and tests a new empirical
equation to generate COHb concentration−time curves. With
this equation and for a given concentration of ambient
CO, one can estimate how much of a subject's hemoglobin
has been tied up as COHb after a given period of exposure.
We believe this to be of value to firefighters, police,
and other emergency personnel.